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Micromelia
Dysmelia (from the Greek (), "bad" + (), "limb" + English suffix -ia) is a congenital disorder of a limb resulting from a disturbance in embryonic development.(2006) Dysmelia (Limb Deficiency/Reduction). pp 312-322. In: Atlas of Genetic Diagnosis and Counseling. Humana Press. Types Dysmelia can refer to * missing (aplasia) limbs: amelia, oligodactyly, congenital amputation e.g. tibial or radial aplasia * malformation of limbs: shortening (micromelia, rhizomelia or mesomelia), ectrodactyly, phocomelia, meromelia, syndactyly, brachydactyly, club foot * too many limbs: polymelia, polydactyly, polysyndactyly * others: tetraamelia, hemimelia, symbrachydactyly Occurrence rate Birth defects involving limbs occur in 1 per 1000. Causes Dysmelia can be caused by * Inheritance of abnormal genes, e.g. polydactyly, ectrodactyly or brachydactyly, symptoms of deformed limbs then often occur in combination with other symptoms (syndromes) * external causes during pregnancy (thus not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meromelia
Meromelia is a birth defect characterized by the lacking of a part, but not all, of one or more limbs with the presence of a hand or foot. It results in a shrunken and deformed extremity. Cause Such defects are mainly the results of genetic disorders, but some teratogenic (or environmental) factors have been identified, such as the use of thalidomide from 1957 to 1962 for morning sickness (NVP). Diagnosis Meromelia a birth defect characterization by the lacking of a part, but all, of one or more limbs with the presence of a hand or foot. Treatment Artificial limbs, surgery, rehabilitation, LASIK Etymology Gk, meros ("part") + melia ("limb") See also * Amelia (birth defect) * Phocomelia * Polymelia * Thalidomide * Amniotic Band Syndrome References Congenital disorders Musculoskeletal disorders Congenital amputations {{congenital-malformation-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syndrome
A syndrome is a set of medical signs and symptoms which are correlated with each other and often associated with a particular disease or disorder. The word derives from the Greek σύνδρομον, meaning "concurrence". When a syndrome is paired with a definite cause this becomes a disease. In some instances, a syndrome is so closely linked with a pathogenesis or cause that the words ''syndrome'', ''disease'', and ''disorder'' end up being used interchangeably for them. This substitution of terminology often confuses the reality and meaning of medical diagnoses. This is especially true of inherited syndromes. About one third of all phenotypes that are listed in OMIM are described as dysmorphic, which usually refers to the facial gestalt. For example, Down syndrome, Wolf–Hirschhorn syndrome, and Andersen–Tawil syndrome are disorders with known pathogeneses, so each is more than just a set of signs and symptoms, despite the ''syndrome'' nomenclature. In other instances, a synd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genes
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a basic unit of heredity and the molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and noncoding genes. During gene expression, the DNA is first copied into RNA. The RNA can be directly functional or be the intermediate template for a protein that performs a function. The transmission of genes to an organism's offspring is the basis of the inheritance of phenotypic traits. These genes make up different DNA sequences called genotypes. Genotypes along with environmental and developmental factors determine what the phenotypes will be. Most biological traits are under the influence of polygenes (many different genes) as well as gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heredity
Heredity, also called inheritance or biological inheritance, is the passing on of traits from parents to their offspring; either through asexual reproduction or sexual reproduction, the offspring cells or organisms acquire the genetic information of their parents. Through heredity, variations between individuals can accumulate and cause species to evolve by natural selection. The study of heredity in biology is genetics. Overview In humans, eye color is an example of an inherited characteristic: an individual might inherit the "brown-eye trait" from one of the parents. Inherited traits are controlled by genes and the complete set of genes within an organism's genome is called its genotype. The complete set of observable traits of the structure and behavior of an organism is called its phenotype. These traits arise from the interaction of its genotype with the environment. As a result, many aspects of an organism's phenotype are not inherited. For example, suntanned skin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polydactyly ECS
Polydactyly or polydactylism (), also known as hyperdactyly, is an anomaly in humans and animals resulting in supernumerary fingers and/or toes. Polydactyly is the opposite of oligodactyly (fewer fingers or toes). Signs and symptoms In humans/animals this condition can present itself on one or both hands or feet. The extra digit is usually a small piece of soft tissue that can be removed. Occasionally it contains bone without joints; rarely it may be a complete functioning digit. The extra digit is most common on the ulnar (little finger) side of the hand, less common on the radial (thumb) side, and very rarely within the middle three digits. These are respectively known as postaxial (little finger), preaxial (thumb), and central (ring, middle, index fingers) polydactyly. The extra digit is most commonly an abnormal fork in an existing digit, or it may rarely originate at the wrist as a normal digit does. The incidence of congenital deformities in newborns is approximately 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Symbrachydactyly
Symbrachydactyly is a congenital abnormality, characterized by limb anomalies consisting of brachydactyly, cutaneous syndactyly and global hypoplasia of the hand or foot. In many cases, bones will be missing from the fingers and some fingers or toes may be missing altogether. The ends of the hand may have "nubbins"—small stumps of soft tissue where the finger would have developed, which may have tiny residual nails. No clear statistics are available regarding the incidence rate for symbrachydactyly. This may be due, in part, to the wide variety of definitions and classifications that are used in diagnosis. In most cases, children born with symbrachydactyly are able to adapt to their physical limitations and experience a fully functional life with no treatment. Most children with this condition can use their hands well enough to do all the usual things children do. Possible treatment includes surgery Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemimelia
Hemimelia comprises the following: * Fibular hemimelia, Congenital longitudinal deficiency of the fibula or fibular longitudinal meromelia * Tibial hemimelia, Congenital longitudinal deficiency of the tibia, Congenital aplasia and dysplasia of the tibia with intact fibula, Congenital longitudinal deficiency of the tibia or tibial longitudinal meromelia * Radial Hemimelia, Congenital longitudinal deficiency of the radius, radial clubhand, radial longitudinal meromelia or radial ray agenesis * Ulnar hemimelia The ulna (''pl''. ulnae or ulnas) is a long bone found in the forearm that stretches from the elbow to the smallest finger, and when in anatomical position, is found on the medial side of the forearm. That is, the ulna is on the same side of the ..., Congenital longitudinal deficiency of the ulna, ulnar clubhand or ulnar longitudinal meromelia References External links {{Phakomatoses and other congenital malformations not elsewhere classified Congenital disorders of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraamelia
Tetra-amelia syndrome (''tetra-'' + '' amelia''), also called autosomal recessive tetraamelia, is an extremely rare autosomal recessive congenital disorder characterized by the absence of all four limbs. Other areas of the body are also affected by malformations, such as the face, skull, reproductive organs, anus, lungs and pelvis. The disorder can be caused by recessive mutations in the WNT3 or RSPO2 genes. Presentation Tetra-amelia syndrome is characterized by the complete absence of all four limbs. The syndrome causes severe malformations of various parts of the body, including the face and head, heart, nervous system, skeleton, and genitalia. In many cases, the lungs are underdeveloped, which makes breathing difficult or impossible. Because children with tetra-amelia syndrome have such serious medical problems, most are stillborn or die shortly after birth. Cause RSPO2 and WNT3 genes Researchers have found loss-of-function mutations in the WNT3 or the RSPO2 genes in people ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polysyndactyly
Polysyndactyly is a congenital anomaly, combining polydactyly and syndactyly, in which affected individuals have an extra finger or toe that is connected, via fusing or webbing, to an adjacent digit. __TOC__ Signs and symptoms Presentations of polysyndactyly vary in location and size of the duplicated digit, and in the extent of webbing between digits. The extra digit is most commonly postaxial, on the same side as the pinky or little toe. Preaxial polysyndactyly, in which the duplicated digit is on the side of the thumb or big toe, is less common. Crossed polysyndactyly, in which polysyndactyly is present on the hand and foot, and is preaxial on one and postaxial on the other, is extremely rare and often occurs with other genetic disorders. Polysyndactyly may be classified by the level of duplication. The extra digit may be small and comprise only soft tissue, but usually includes at least one bone, most commonly the distal and middle phalanges. Partial or complete duplica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polydactyly
Polydactyly or polydactylism (), also known as hyperdactyly, is an anomaly in humans and animals resulting in supernumerary fingers and/or toes. Polydactyly is the opposite of oligodactyly (fewer fingers or toes). Signs and symptoms In humans/animals this condition can present itself on one or both hands or feet. The extra digit is usually a small piece of soft tissue that can be removed. Occasionally it contains bone without joints; rarely it may be a complete functioning digit. The extra digit is most common on the ulnar (little finger) side of the hand, less common on the radial (thumb) side, and very rarely within the middle three digits. These are respectively known as postaxial (little finger), preaxial (thumb), and central (ring, middle, index fingers) polydactyly. The extra digit is most commonly an abnormal fork in an existing digit, or it may rarely originate at the wrist as a normal digit does. The incidence of congenital deformities in newborns is approximately 2%, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymelia
Polymelia is a birth defect in which an affected individual has more than the usual number of limbs. It is a type of dysmelia. In humans and most land-dwelling vertebrates, this means having five or more limbs. The extra limb is most commonly shrunken and/or deformed. The term is from Greek πολυ- "many", μέλεα "limbs". Sometimes an embryo started as conjoined twins, but one twin degenerated completely except for one or more limbs, which end up attached to the other twin. Sometimes small extra legs between the normal legs are caused by the body axis forking in the dipygus condition. Notomelia (from Greek for "back-limb-condition") is polymelia where the extra limb is rooted along or near the midline of the back. Notomelia has been reported in Angus cattle often enough to be of concern to farmers. Cephalomelia (from Greek for "head-limb-condition") is polymelia where the extra limb is rooted on the head. Origin Tetrapod legs evolved in the Devonian or Carboniferous geo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
